透明MgO·nAl_(2)O_(3)尖晶石陶瓷雾度分析  

Analysis of Haze in Transparent MgO·nAl_(2)O_(3) Spinel

作　　者：庞珍丽[1] 李祯[1] 王立弟[1] 田庭燕[2] PANG Zhenli;LI Zhen;WANG Lidi;TIAN Tingyan(Brightcrystals Technology Inc.,Beijing 100018,China;Beijing Sinoma Synthetic Crystals Co.,Ltd.,Beijing 100018,China)

机构地区：[1]烁光特晶科技有限公司,北京100018 [2]北京中材人工晶体研究院有限公司,北京100018

出　　处：《人工晶体学报》2021年第8期1408-1412,共5页Journal of Synthetic Crystals

基　　金：国家重点研发计划(2017YFB0310500)。

摘　　要：以高纯超细粉体为原料,采用热压(HP)结合热等静压(HIP)法制备了透明MgO·nAl_(2)O_(3)(n=0.98、1、1.1、1.2、1.3)尖晶石陶瓷。雾在透明陶瓷中十分常见,严重云雾的存在大幅降低透光率,影响陶瓷的力学性能。为了获得光学质量优异、力学性能适宜的MgO·nAl_(2)O_(3)尖晶石,对尖晶石中的雾度进行了测量,并对雾的形成进行了分析。通过扫描电镜(SEM)发现,在雾较重的富镁半透明样品中,晶界处有许多圆形晶粒。用能谱仪(EDS)测定了圆形晶粒的组成为n=0.41。第二相MgO由于镁过量而易析出,严重降低了晶界强度,影响陶瓷的力学性能。MgO相与尖晶石相具有不同的折射率,会引起严重的光散射,降低样品的透过率。在另一试样中,测得晶界处颗粒组成为n=1.33,测得该富铝试样的抗弯强度远远高于n=1试样和富镁试样。In this paper,transparent MgO·nAl_(2)O_(3)(n=0.98,1,1.1,1.2,1.3)spinel ceramics were prepared from high pure and ultra fine powder by hot pressing(HP)and hot isostatic press(HIP).Haze is very common in transparent ceramics,its presence greatly reduces transmittance and affects mechanical properties of ceramics.In order to obtain MgO·nAl_(2)O_(3) spinel with high optical quality and suitable mechanical properties,the haze in spinel was measured and the haze formation was analyzed.It is found that many circular particles at the grain boundaries in the translucent Mg-rich samples with dense haze by SEM.The composition of the circular particles was measured to be n=0.41 by EDS.The second phase MgO is readily precipitated due to the extra magnesium,that will seriously reduce the grain boundary strength and affect the mechanical properties of ceramics.The residual MgO phase has different refractive index with spinel phase,which can cause serious light scattering and reduce the transmittance of the sample.The composition of the particles at the grain boundary was measured to be n=1.33 in another sample,the flexure strength of this Al-rich sample was measured is much higher than that of stoichiometric and Mg-rich samples.

关 键 词：MgO·nAl_(2)O_(3) 尖晶石 雾度 抗弯强度 透明陶瓷 热等静压 

分 类 号：TQ174.75[化学工程—陶瓷工业]